https://nexus.keylightdigital.dev/blog Articles on AI agent observability, monitoring, and building in public. en-us Tue, 14 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/claude-code-agent-observability https://nexus.keylightdigital.dev/blog/claude-code-agent-observability Claude Code agents run long, multi-step tasks — and when they fail, you want to know exactly where. Here's how to wrap Claude Code tool executions in Nexus traces so every agent run is fully observable: what happened, how long each step took, and what failed. Tue, 14 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/ai-agent-reliability-patterns https://nexus.keylightdigital.dev/blog/ai-agent-reliability-patterns AI agents fail differently from traditional software. Retry storms burn your token budget. Silent timeouts leave traces hanging. Circuit breakers prevent cascading LLM failures. Here are four battle-tested reliability patterns — with trace examples showing what each looks like in Nexus. Tue, 14 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/reduce-ai-agent-costs https://nexus.keylightdigital.dev/blog/reduce-ai-agent-costs Running AI agents in production gets expensive fast. We went from $800/month to $310/month on LLM costs — without reducing quality. Here's the trace-driven approach we used: identifying the spans burning the most tokens, eliminating unnecessary retries, and caching repeated context. Tue, 14 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/detecting-ai-hallucinations https://nexus.keylightdigital.dev/blog/detecting-ai-hallucinations Hallucinations are the silent killers of AI agent reliability. Most teams only discover them from user complaints. Here's how to use trace analysis to detect hallucinations before they reach your users — with output verification spans, confidence scoring, and retrieval comparison tracing. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/multi-agent-observability-patterns https://nexus.keylightdigital.dev/blog/multi-agent-observability-patterns Multi-agent systems fail in ways that single-agent monitoring can't catch: delegation chains where blame is unclear, consensus races, hierarchical orchestration bugs. Here are 4 patterns with instrumentation approaches for each. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/choose-ai-observability-tool https://nexus.keylightdigital.dev/blog/choose-ai-observability-tool Evaluating AI observability tools? Most comparisons list features without helping you decide. Here's a practical buyer's guide: 5 criteria that actually matter, a decision matrix by team size, and common mistakes to avoid. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/ai-agent-cost-guide https://nexus.keylightdigital.dev/blog/ai-agent-cost-guide Running AI agents in production costs more than most teams expect. Token costs compound quickly across retries, context overflows, and unnecessary tool calls. Here's how to calculate realistic costs, identify hidden cost patterns, and use tracing to keep your bill predictable. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/opentelemetry-ai-agents https://nexus.keylightdigital.dev/blog/opentelemetry-ai-agents OpenTelemetry is great at instrumenting web services. But AI agents fail in ways that standard spans and metrics were never designed to capture. Here's what OTEL gets right, five things it misses, and how purpose-built agent observability fills the gaps. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/langchain-tracing-tutorial https://nexus.keylightdigital.dev/blog/langchain-tracing-tutorial A step-by-step tutorial for adding Nexus observability to a LangChain agent. Install the SDK, create an API key, wrap your agent with traces and spans, and see execution in your dashboard — in under 5 minutes. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/ai-agent-metrics https://nexus.keylightdigital.dev/blog/ai-agent-metrics Most teams monitoring AI agents track the wrong things. Here are the five metrics that actually predict production problems — latency percentiles, token cost per request, error rate by tool, trace completion rate, and context utilization — with Nexus SDK examples. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/ai-observability-tools-compared https://nexus.keylightdigital.dev/blog/ai-observability-tools-compared Langfuse, LangSmith, Helicone, Braintrust, Arize Phoenix, AgentOps, or Nexus? A practical breakdown of every major AI agent observability tool — what each one does best, where it falls short, and how to choose. Thu, 09 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/debugging-ai-agents-in-production https://nexus.keylightdigital.dev/blog/debugging-ai-agents-in-production AI agents fail in non-obvious ways: tool call errors that cascade silently, context windows that overflow mid-task, loops that spin without terminating. Here's a practical debugging playbook with trace-first strategies and Nexus SDK examples. Tue, 07 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/autonomous-agent-observability https://nexus.keylightdigital.dev/blog/autonomous-agent-observability Ralph is the AI agent that built Nexus. It monitored itself throughout. Here are the failure modes we caught from trace data, and the design principles that emerged from 84 user stories and hundreds of agent sessions. Wed, 08 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/monitoring-rag-pipelines https://nexus.keylightdigital.dev/blog/monitoring-rag-pipelines RAG pipelines fail in subtle ways: bad retrievals, context stuffing, hallucinations from irrelevant chunks. Here's what to monitor, what metrics matter, and how to trace retrieval and generation steps with Nexus. Tue, 07 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/monitor-ai-agents-production https://nexus.keylightdigital.dev/blog/monitor-ai-agents-production AI agents fail in production in ways that are invisible without observability. Silent retries, cascading tool errors, runaway token usage — here's how to instrument your agents before they cost you. Tue, 07 Apr 2026 00:00:00 GMT https://nexus.keylightdigital.dev/blog/introducing-nexus https://nexus.keylightdigital.dev/blog/introducing-nexus We built Nexus because we needed it. An AI agent (Ralph) needed a way to monitor itself. Here's the story of what we built, how it works, and why we're open-sourcing it. Mon, 06 Apr 2026 00:00:00 GMT